I messed up

I may have won the game, but i feel like I played "bad" chess. And im sure that he would have won if he played smarter

I think 3 ...Nc6 or d6 was better because after 3 ...Nf6 4. Nxe5. 6 ...d5 seems bad to me as it loses the d-pawn. Better is probably 6 ...Nc6 with tempo or perhaps even 6 ...d6. I see your idea of playing 7 ...Be6 but I think if white had played 8. Bg5 you would have lost that pawn without anything you could do about it. 8 ...Nc6 loses a piece by force I think. I too think 13. Qxc4 is better for white. White got too greedy with 15 Bxc7. Probably should have just castled. 15 bxc5 looks like it loses for white. But you did a good job making white pay for his greed on move 15. Grats.

Thank you for your excelent comments

So many blunders, but anyway, you are correct 15. Qxc7 is absolutely senseless, had he just quitely castled at move 15. He'd have had to bluder every move to lose.

Playing 15. Qxc7 means he not only missed his hanging f2 pawn, but also the hanging black Knight at c4.

On move 9 you definitely shouldn't have played Ng4 with a pawn fork sitting there and the consequences of him losing the queen no longer being there. 

There are two reasons to chase a queen: to trap it and win it, or to gain a tempo for your own threats. Ng4 accomplishes neither, maybe if you had prepped it with Qf6 but that was also impossible with the fork. Which is why GM Ben Finegold reminds us that it's painful to walk into forks. 

mmm. Well for starters 3... d6 is the only good move on the board. 3... Nf6 falls into an immediate 4. Nxe5 and 3... Nc6 also falls into 4. Nxe5 Nxe5 5. d4 and White will be in a better position. No need to give away the bishop early after 5... Bxd4  you should try to keep your bishop on the board in the opening. Do not go trading it off for a knight so quickly unless forced or you are trading a bad bishop for a good knight (For example in the French advance, if you can somehow exchange the light squared bishop, Black is doing great) Also now after 6.Qxd4  especially in the scotch, when White has a queen on d4, the computer usually gives a 1.5 advantage to White! So in the scotch, do not trade that dark colour bishop. Again 6... d5? again is losing a pawn. 6... Nc6 would be attacking the queen and it is not so bad for Black. You also had an interesting idea 8...c6!? could possibly win you the d5 pawn. That was your best try but 8...Nc6?? Then loses a piece likewise what happened in the game. 12... fxe6? AGAIN loses another piece, although your position is already hard to deal with now. 12... Nd6!? Another interesting idea is your best try after 13. Qxg7 Rf8 14. Bg5 falls into f6 so he will play 14. 0-0 Qe7 followed by 0-0-0, but the game is very bad for Black. At an U1200 level, you still have chances. 14... Qh4?! is interesting but dubious. I am so shocked that nobody saw that Black wins the game quicker at move 16 16... Rd8+! but after 16... Qd4+ 17. Ke2, Black will eventually mate.

So, key points to learn from this game:

Be careful of Nxe5 ideas in this line

Try to avoid exchanging bishops for knights in openings unless their knight is better than your bishop

Never take the knight on d4 in the scotch even if you have a knight on c6

Just be aware that you are hanging a piece but your opponent cannot take it because of the pin, Make sure you pay attention if he has anything to remove the piece from the Pin (Removal of the pin) Something to keep in mind

Follow these tips, you will go fine.

Good Luck